We're making the transition from the soft-topped sippy cup to the hard ones with Elias right now, and so to make it more appealing, I got some that have one of Elias' favorite things right now on them: cars. Specifically, they're NASCAR sippy cups with Jimmie Johnson, Justin's favorite driver.
Elias already had two toy Jimmie cars, which he LOVES to play with. He says "Vroooooom!" So he instantly recognized it as "Jimmie car" when he saw it on his sippy. We're so proud!
Right now he's using it without the spill-proof valve, but it doesn't have a vent hole, so it's remarkably spill-proof even without the valve. He does well with it, though.